One of the best games for the 3DS is a game that could easily have been done on the regular DS, gameplay-wise.
Seriously, the graphics are functional at best. Don't be fooled by them. While it would've been nice to see a little more polish on them - they'd be barely acceptable in a first-gen PSP game - they do their job for this game. You never question what you're looking at, which is what's important in Shadow Wars. Because this is personal turn-based, grid-based strategy at its peak.
You only ever control a handful of units. Sometimes you get some extra units in addition to your party of six unique classes, sometimes you're stuck picking just a party of four. The good thing about this is that everyone's role IS very defined. You really have to think about where to send each of your squad, and the game will punish you if you send someone out on a solo mission.
At least, it will if you're playing on the Hard level. And you will want to. The game is, with some small exceptions, downright easy at the regular difficulty level. You can tell that it really was meant to be played at the hard difficulty level: Some classes are downright abuseable at the regular level, to the point where you can take one particular character and go on a rampage with them, taking down half the enemy force before they even have a chance to move.
Play at the harder difficulty level, though, and it becomes a game of careful decisions, nail-biting victories, and really playing to each of your characters' strengths. It very rarely turns into a game of trial and error - the game likes to trigger sudden ambushes as you complete objectives, and so you'll want to spend an extra turn just to have everyone ready to move as you complete an objective - but planning ahead means that the game will almost always feel tough, but fair.
It's also a fairly long game, to the point that, granted, you might lose interest before it ends. The story's largely ignorable. The upside is that you'll have played for a good 10-20 hours before you've had your fill, and if you're really hooked, you've got a few more hours of story missions to do after that, and a LOT of bonus missions to complete on the story maps after that's done. There's a ton of gameplay here, no question about it.